The effect of porosity and number of unit cell on applicability of volume average approach in closed cell porous media
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 20 December 2021
Issue publication date: 17 June 2022
Abstract
Purpose
The purpose of this study is to investigate the applicability of volume average which is extensively used for analyzing the heat and fluid flow (both for single-phase and solid/liquid-phase change) in a closed cell porous medium numerically.
Design/methodology/approach
Heat conduction equations for the solid frame and fluid (or phase change material) are solved for pore scale and volume average approaches. The study mainly focuses on the effect of porosity and the number of porous media unit cell on the agreement between the results of the pore scale and volume average approaches.
Findings
It is observed for the lowest porosity values such as 0.3 and the number of porous media unit cell as 4 in heat transfer direction, the results between two approaches may be questionable for the single-phase fluid. By increasing the number of porous media unit cell in heat transfer direction, the agreement between two approaches becomes better. In general, for high porosity values (such as 0.9) the agreement between the results of two approaches is in the acceptable range both for single-phase and solid/liquid-phase change. Two charts on the applicability of volume average method for single-phase and solid/liquid-phase change are presented.
Originality/value
The authors’ literature survey shows that it is the first time the applicability of volume average which is extensively used for analyzing the heat and fluid flow in a closed cell porous medium is investigated numerically.
Keywords
Acknowledgements
This work was supported by The National Science Fund for Distinguished Young Scholars [grant number 51925604]; the National Natural Science Foundation of China [grant number 51976215]; the Scientific Instrument Developing Project of the Chinese Academy of Sciences [grant numbers YJKYYQ20200017, YZ201615]; and the Funding of Innovation Academy for Light-duty Gas Turbine, Chinese Academy of Sciences [grant number CXYJJ20-MS-01].Chunyang Wang and Xinghua Zheng contributed equally to this work.
Citation
Wang, C., Zheng, X., Zhang, T., Chen, H. and Mobedi, M. (2022), "The effect of porosity and number of unit cell on applicability of volume average approach in closed cell porous media", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 32 No. 8, pp. 2778-2798. https://doi.org/10.1108/HFF-08-2021-0527
Publisher
:Emerald Publishing Limited
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